In vitro and in vivo N-acetylation of carcinogenic glutamic acid pyrolysis products in humans

The carcinogenic glutamic acid pyrolysis products, 2-amino-6-methyldipyrido [1,2-a:3',2'-d]imidazole (Glu-P-1) and 2-aminodipyrido [1,2-a:3',2'-d]imidazole (Glu-P-2), and their N-acetyl derivatives have been demonstrated to be present in human urine, bile, liver and kidney. In vitro experiments have revealed that Glu-P-1 and Glu-P-2 are N-acetylated to form N-acetyl derivatives by the cytosolic fraction from a human autopsy liver specimen. From these results our data strongly suggest that Glu-P-1 and Glu-P-2 derived from everyday foods are partially N-acetylated in human organs and that they are excreted in bile and urine with their N-acetyl derivatives. Our data also provide the first reliable evidence that humans can metabolize the carcinogenic heterocyclic amines.